1. Field of the Invention
The present invention relates to a camera, and particularly to a camera having a barrier that is slidable between a position in which it keeps a taking lens covered and a position in which it leaves the taking lens uncovered.
2. Description of the Prior Art
In a camera, a barrier slides between a fully-closed position in which it covers the front-end surface of a taking lens and a fully-open position in which it is retracted from the front-end surface of the taking lens. In this way, the barrier serves to protect the taking lens when no shooting is performed and, in some cases, also serves as a starting switch to make the camera system ready for shooting. FIG. 6 is a schematic perspective view showing a conventional example of the structure of such a barrier.
As shown in FIG. 6, a barrier 3 has two, upper and lower, rails 40 and 41 provided integrally therewith, and these rails 40 and 41 are held between a plurality of rotatable guide rollers 8 or the like provided integrally with a body cover 2 of a camera 1. The rails 40 and 41 are linearly guided by these guide rollers 8 so that the barrier 3 slides across the front-end surface of a taking lens L. Moreover, a click roller 7 is provided that is pressed against one of the rails 40 from above by a compression spring 6 or the like so as to be slidable by rotation along the rail 40. When the barrier 3 is in a fully-open position or in a fully-closed position, this click roller 7 engages with an engagement groove 40a or 40b, respectively, formed in the rail 40 so as to exert a clicking force in those two positions.
However, as long as such a sliding mechanism is used to slide the barrier 3, as the camera is made more compact, the rails 40 and 41 need to be made shorter so as not to protrude from the barrier 3. Correspondingly, the intervals between the guide rollers 8a and 8b and between the guide rollers 8c and 8d need to be made shorter so that the rails 40 and 41 will not come off the guide rollers 8 when the barrier 3 is in the fully-open position.
Between the guide rollers 8a, 8b, 8c, and 8d and the rails 40 and 41, there are secured gaps that allow the rails 40 and 41 to slide, and thus the barrier 3 is somewhat inclined while sliding. Accordingly, making the intervals between the guide rollers 8a and 8b and between the guide rollers 8c and 8d shorter causes the barrier 3 to be more inclined while sliding. This makes the sliding movement of the barrier 3 unstable, and thereby degrades the feel of operation of the camera.
Moreover, though not shown in FIG. 6, it is necessary to separately provide positioning members to restrict the movement of the barrier 3 in the front-rear direction of the camera so as not to come off the body cover 2. This increases the number of components required, and thus increases the overall costs.